Method and Apparatus for Performing Data Buffering for Reed-Solomon (r-S) Coding/Decoding in a Mobile Communication System

1. A method for performing data buffering for Reed-Solomon (R-S) coding in a transmitter of a mobile communication system supporting a broadcast and multicast (BCMC) service, the method comprising: determining whether a format change exists in a broadcast overhead message (BOM) comprising information of a position of data for the BCMC service; calculating a change position of data in a block buffer at a time when the BOM is changed; and filling the block buffer with predetermined data ranging from a start point of the block buffer to the calculated changed position of data first transmitted according to the changed BOM.

2. The method of claim 1 , wherein the predetermined data filled in the block buffer comprises a bit predefined by the transmitter and a receiver supporting the BCMC service.

3. The method of claim 1 , further comprising, determining whether data before a TDM (Time Division Multiplexing) information change in the BOM overlaps with data after the TDM information change in the BOM; and if the data before and after the TDM information change in the BOM does not overlap each other, filling the block buffer with the predetermined data ranging from a point following a point of data last transmitted to a block buffer before the TDM information change in the BOM to the calculated changed position of data first transmitted to the block buffer after the TDM information change in the BOM, while maintaining the block buffer.

4. An apparatus for performing data buffering for Reed-Solomon (R-S) coding in a transmitter including an outer encoder for encoding logical channel bits into logical channel symbols for a mobile communication system supporting a broadcast and multicast (BCMC) service, the apparatus comprising: a block buffer for buffering data; and a controller for determining whether a format change exists in a broadcast overhead message (BOM) comprising information of a position of data for the BCMC service, calculating a change position of data in a the block buffer at a time when the BOM is changed, and filling the block buffer, immediately after a change point in the BOM, with predetermined data ranging from a start point of the block buffer to the calculated changed position of data first transmitted according to the changed BOM.

5. The apparatus of claim 3 , wherein the predetermined data filled in the block buffer comprises a bit predefined by the transmitter and a receiver supporting the BCMC service.

6. The apparatus of claim 4 , wherein the controller is further configured to determine whether data before a TDM (Time Division Multiplexing) information change in the BOM overlaps with data after the TDM information change in the BOM, if the data overlaps each other, fill the block buffer with the predetermined data in the first interval after performing the erasure process, and if the data before and after the change in the BOM does not overlap each other, fill the block buffer with the predetermined data ranging from a point following a point of data last transmitted to the block buffer before the TDM information change in the BOM to the calculated changed position of data first transmitted to the block buffer after the TDM information change in the BOM, while maintaining the block buffer.

7. A method for performing data buffering for Reed-Solomon (R-S) decoding in a receiver of a mobile communication system supporting a broadcast and multicast (BCMC) service, the method comprising: determining whether a format change exists in a broadcast overhead message (BOM) comprising information of a position of data for the BCMC service; calculating a position of data in a block buffer at a time when the BOM is changed; performing an erasure process, until the change point of the BOM, on data that a the block buffer failed to receive; and filling the block buffer, immediately after the format change in the BOM, with predetermined data ranging from a start point of the block buffer to the calculated changed position of data first received according to the changed BOM.

8. The method of claim 7 , wherein the predetermined data comprises a bit predefined by a transmitter and the receiver supporting the BCMC service.

9. The method of claim 7 , further comprising, determining whether data before a TDM (Time Division Multiplexing) information change in the BOM overlaps with data after the TDM information change in the BOM; and if the data before and after the TDM information change in the BOM does not overlap each other, filling the block buffer with data ranging from a point following a point of data last received in the block buffer before the TDM information change in the BOM to the calculated changed position of data first received in the block buffer after the TDM information change in the BOM, while maintaining the block buffer without the erasure process.

10. An apparatus for performing data buffering for Reed-Solomon (R-S) decoding in a receiver including an outer decoder for decoding at least one logical channel symbol into at least one logical channel bit for a mobile communication system supporting a broadcast and multicast (BCMC) service, the apparatus comprising: a block buffer for buffering data; and a controller for determining whether a format change exists in a broadcast overhead message (BOM) comprising information of a position of data for the BCMC service, calculating a position of data in the block buffer at a time when the BOM is changed, performing an erasure process, until a change point of the BOM, on data that the block buffer failed to receive and filling the block buffer, immediately after the change point in the BOM, with predetermined data ranging from a start point of the block buffer to the calculated changed position of data first received according to the changed BOM.

11. The apparatus of claim 10 , wherein the predetermined data comprises a bit predefined by a transmitter and the receiver supporting the BCMC service.

12. The apparatus of claim 10 , wherein the controller is further configured to determine whether data before a TDM (Time Division Multiplexing) information change in the BOM overlaps with data after the TDM information change in the BOM, if the data overlaps each other, fill the block buffer with the predetermined data in the first interval after performing the erasure process, and if the data before and after the change in the BOM does not overlap each other, fill the block buffer with the predetermined data ranging from a point following a point of data last received in the block buffer before the TDM information change in the BOM to the calculated changed position of data first received in the block buffer after the TDM information change in the BOM without the erasure process, while maintaining the block buffer.